My son has one; he has Endler's (he does have a mix of male and females, but that's because I have plenty of spare tank space if there are too many fry; if it's your only tank, you
must get males only, or you'll get overstcoked very, very rapidly!), a couple of ghost shrimp and an assassin snail (because there are pest snails in there from the plants I donated
)
Other good inhabitants would be; sparkling gourami, featherfin rainbows, dwarf emerald rasboras, chilli rasboras, celestial pearl danios, ember tetras.
Avoid anythiong that grows to over an inch, and anything that has horizontal stripes, as they'll be fast swimmers that need more room than an Edge can provide; zebra danios and WCMM, for instance.
I wouldn't recommend them for a first tank, though; they're tricky to maintain and I think you need a bit of previous experience to keep one; a standard tank is far easier for newcomers to the hobby.